Compensated motion base

ABSTRACT

A compensated actuator, in various embodiments, comprises a base and an electric actuator and a fluid actuator interconnected to cooperatively allow for movement of an upper deck frame to which one or more compensated actuators are connected with or without using a pivoting connector. When so connected, a predetermined set of compensated actuators are connected to the upper deck frame and a platform intermediate the upper deck frame and the platform in a predetermined pattern and linear forces from the electric actuator and fluid actuator combined to impart rotation to an output attachment point.

RELATION TO PRIOR APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 15/650,421, now granted, which was a divisional application of U.S.application Ser. No. 14/735,592, now U.S. Pat. No. 9,829,149, and claimsthe benefit of, and priority through, U.S. Provisional Application62/008,123, titled “Compensated Motion Base,” filed Jun. 10, 2014.

FIELD OF THE INVENTION

The invention relates generally to positioning devices that move apayload via actuators.

BACKGROUND OF THE INVENTION

A compensated motion base is a vertical positioning device that movesits payload via actuators through multiple degrees of freedom (DOF) suchas pitch, roll, heave, and/or yaw. Compensated motion bases may be usedwith small payload systems such as for scientific and/or medical uses;amusement or other ride vehicles; stationary simulators; large theaters;military and aircraft trainers; or the like, or combinations thereof.

FIGURES

The figures supplied herein disclose various embodiments of the claimedinventions.

FIG. 1 is view in partial perspective of an exemplary embodiment of acompensated actuator;

FIG. 2 is view in partial perspective of an exemplary embodiment of acompensated motion base illustrating a compensated actuator and upperdeck frame;

FIG. 3 is view in partial perspective of an exemplary embodiment of acompensated motion base;

FIG. 4 is view in partial perspective of a further exemplary embodimentof a compensated actuator in a first position; and

FIG. 5 is view in partial perspective of a further exemplary embodimentof a compensated actuator in a second position.

DESCRIPTION OF VARIOUS EMBODIMENTS

As used herein, a set may comprise one or more elements, e.g. a set ofcompensated actuators 10 may be just one compensated actuator 10 or anynumber of compensated actuators 10. Each joint, as will be apparent toone of ordinary skill in the motion base arts, may be a spherical joint,a clevis joint, a ball joint, or the like. A pivoting connection isunderstood to include a hinged or other pivoting connection. Further,one of ordinary skill in the motion base arts would understand that apneumatic actuator is used with a gas and a hydraulic actuator is usedwith hydraulic fluid. Accordingly, the term “fluid actuator,” as usedherein, covers either as the context requires, e.g. a fluid actuatorused with gas as its fluid is a pneumatic actuator and a fluid actuatorused with a liquid or similar hydraulic fluid as its fluid is ahydraulic actuator.

Referring now to FIG. 1, in a first embodiment, compensated actuator 10comprises pivoting connector 70, base 40, electric actuator 20, andfluid actuator 30.

Pivoting connector 70 comprises output attachment point 72 configured tobe pivotally attached to a payload-bearing main deck 80 (FIG. 2), firstjoint 78, and second joint 79. In an embodiment, pivoting connector 70is used to combine linear forces and impart rotation to outputattachment point 72. As will be apparent to those of ordinary skill inthe motion base arts, pivoting connector 70 pivots and/or is hinged withrespect to base 40.

Base 40 typically comprises two or more attachment points by which base40 can be connected to a further structure, e.g. platform 82 (FIG. 3).By way of example and not limitation, base 40 may comprise one or morefirst attachment points 41 configured to be connectable to a firstpredetermined location, by way of example and not limitation such asproximate a center point of platform 82, and one or more secondattachment points 42 configured to be connectable to a secondpredetermined location, such as by way of example and not limitationproximate an outer perimeter of platform 82. Base 10 further comprisesone or more linear actuator joints 43, one or more fluid actuator joints45, and one or more connector joints 44 configured to accept pivotingconnector 70 such as at pivot 15 and allow pivoting connector 70 to bepivoted or hinged with respect to base 40.

Electric actuator 20 is cooperatively and pivotally connected topivoting connector 70 at first joint 22 and first connector joint 78 andpivotally connected to base 40 at linear actuator joint 43 via firstbase joint 23. This arrangement combines the retractive force ofelectric actuator 20 with the extensive force of fluid actuator 30,resulting in the powered raising of pivoting connector 70 with respectto output joint 72. It also combines the extensive force of electricactuator 20 with the retractive force of fluid actuator 30, resulting inthe powered lowering of output attachment point 72. However, electricalactuator 20 may be operatively linked to fluid actuator 30 and outputattachment point 72 a variety of ways, depending on the desiredorientation of actuators 20,30 and the direction of force to bedelivered by output attachment point 72. Further, electric actuator 20and fluid actuator 30 may be positioned on the same side of axis 44, sothat the extensive and retractive forces of both actuators are acting inthe same direction.

In typical embodiments, electrical actuator 20 is a separate componentwith respect to fluid actuator 30 and may comprise a linear electricalactuator or a rotary electrical actuator or the like. In otherembodiments, electrical actuator 20 may be positioned within inflatablefluid actuator 30. In certain embodiments, electrical actuator 20 andfluid actuator 30 are an integrated device, such as where both arecoaxial and share a coupled or common shaft.

Fluid actuator 30 is cooperatively connected to electric actuator 20 bybeing pivotally connected to connector 70 at second joint 25 and secondconnector joint 79 and pivotally connected to base 10 at fluid actuatorjoint 45 via second base joint 24. Fluid actuator 30 may comprise apassively pressurized fluid actuator, an inflatable fluid actuator suchas an air bag or air stroke actuator, or the like.

Compensated actuator 10 may further comprise fluid supply tank 60 (FIG.2) operatively in fluid communication with fluid actuator 30 andconfigured to provide a predetermined spring rate for fluid actuator 30,e.g. a substantially constant spring rate.

Referring now to FIGS. 2 and 3, in a further embodiment, compensatedmotion base 1 comprises upper deck frame 50, comprising predeterminedouter perimeter 53, platform 82, and a set of compensated actuators 10disposed intermediate upper deck frame 50 and platform 82 and arrangedin a predetermined pattern. Each compensated actuator 10 of the set ofcompensated actuators 10 is as described above, and at least oneactuator 10 of the set of compensated actuators 10 is operativelyconnected to upper deck frame 50 via one or more corresponding pivotingconnectors 70.

Referring additionally back to FIG. 1, for this embodiment, connector 70may further comprise pivot junction 74, first extension 76 extendingaway from pivot junction 74 where first extension 76 comprises outputattachment point 72 and is configured to be pivotally or hingedlyconnected to upper deck frame 50, and second extension 73 extending awayfrom pivot junction 74 at a predetermined offset from first extension76. Second extension 72 typically comprises first connector joint 78 andis configured to be connected to an associated linear actuator 20 of thegroup of actuators at first joint 22 and first connector joint 78.Pivoting connector 70 further comprises hinge 77 defined at a meetingjunction of first extension 76 and second extension 72 where hinge 77comprises second connector joint 79.

Referring additionally to FIGS. 4 and 5, in additional embodimentspivoting connector 70 may further comprise one or more support brackets93, at least one of which comprises pivot junction 96; one or moresupport arms 94 connected to at least one support bracket 93, at leastone support arm 94 being further pivotally connected to first extension76 at support arm pivot connector 95, and pivot 91 pivotally connectedto at least one of the support brackets 93 at pivot junction 96 wherepivot 91 is configured to be connected to upper deck frame 50 at supportconnector 90.

First attachment point 41 (FIG. 1) is configured to be connectable to apredetermined location proximate the center point of platform 82 andsecond attachment point 42 is configured to be connectable to apredetermined location proximate an outer perimeter of platform 72.

In various embodiments, a set of fluid supply tanks 60 may be presentbut are not required. If present, one or more fluid supply tanks 60 areoperatively in fluid communication with one or more corresponding fluidactuators 30 and configured to provide a predetermined spring rate forits corresponding fluid actuator 30. In embodiments, the predeterminedspring rate comprises a substantially constant spring rate.

Upper deck frame 50 and platform 82 may comprise any shape. By way ofexample and not limitation, if several degrees of freedom are desired,upper deck frame 50 may comprise a triangular outer perimeter and theset of compensated actuators 10 may comprise three or more compensatedactuators 10. Typically, each compensated actuator 10 is arranged evenlyand radially outward from proximate a center point of platform 82 orupper deck 50 to a predetermined triangular junction point on outerperimeter 53. One or more output attachment points 72 may be configuredto be pivotally attached to upper deck frame 50 and/or payload-bearingdeck 80, operatively connected to upper deck frame 50, proximate atriangular junction point on outer perimeter 53. In such configurations,the corresponding set of fluid supply tanks 60 may comprise three fluidsupply tanks 60, each fluid supply tank in fluid communication with acorresponding compensated actuator 10.

Typically, compensated motion base 1 is configured to provide multipledegrees of freedom. By way of example and not limitation, compensatedmotion base 1 may implement a pitch or roll platform, e.g. one thatpivots, and at least one compensated actuator 10 of the set ofcompensated actuators 10 is operatively connected to the pitch or rollplatform. However, other configurations are also contemplated. By way offurther example and not limitation, upper deck frame 50 and/orpayload-bearing deck 80 may comprise a circular, substantiallyrectangular, or obround outer perimeter 53. Further, the set ofcompensated actuators 10 may comprise just one actuator configured toprovide a sole degree of freedom of movement. In other embodiments, twocompensated actuators 10 may be deployed at points proximate a singleside of substantially rectangular or obround outer perimeter, where anopposing side is hinged or otherwise secured to platform 82 and severaldegrees of freedom of movement may be achieved. In yet otherconfigurations, upper deck frame 50 may comprise a substantially roundouter perimeter and the set of compensated actuators 10 may comprisemultiple compensated actuators 10 by which several degrees of freedom ofmovement may be achieved.

In a further embodiment, connector 70 is not used. Instead, compensatedmotion base 1 may comprise upper deck frame 50, comprising apredetermined outer perimeter 53, platform 82, and a set of compensatedactuators 10 arranged in a predetermined pattern, by way of example andnot limitation evenly and radially outward from proximate a center point51 of upper deck frame 50 or platform 82 to outer perimeter 53. Althoughsimilar to the above described configurations, in this embodiment one ormore electric actuators 20 is pivotally connected to base 40 at basecoupler 43 via first base joint 43 and pivotally connected to upper deckframe 50 at a first joint 22, The corresponding fluid actuator 30 ispivotally connected to base 40 at second base joint 45 and to upper deckframe 50 at or proximate to first joint 22, e.g. with second joint 25,so as to be cooperatively connected to electric actuator 20. In thisembodiment, first joint 22 and second joint 25 may be substantiallyco-located.

In embodiments where both actuators 20,30 are vertical, and thereforepushing between a common base and upper attachment, an alternativestructure, e.g. a scissor lift or the like, may be used to providehorizontal guidance and prevent a load such as platform 50 or the entirecompensated motion base 1 from falling over. Thus, a scissor lift orsimilar mechanism, e.g. vertical rails, rollers, or the like, or acombination thereof, may be used at one or more actuator groups 10.

As with the other embodiments, a set of fluid supply tanks 60 may bepresent with each fluid supply tank 60 of the set of fluid supply tanks60 being operatively in fluid communication with a corresponding fluidactuator 30 and configured to provide a substantially constant springrate for each connected fluid actuator 30.

In the operation of exemplary embodiments, typically electrical actuator20, whether linear or rotary, is coupled between platform 82 and amovable load, e.g. on disposed on upper deck frame 50 and/orpayload-bearing deck 80. The movable load is compensated, e.g.partially, for by an additional force in the form of fluid gas orhydraulic pressure.

Accordingly, compensated motion base 1 may be provided by coupling apredetermined set of compensated actuators 10 to upper deck frame 50 andplatform 82 as described above. If present, pivoting connectors 70 maybe used to combine the linear forces from electric actuator 20 and fluidactuator 30 and, as a result, impart rotation to output attachment point72.

As described above, the set of compensated actuators 10 is arranged in apredetermined pattern such as evenly and radially outward from proximatea center point 51 of upper deck frame 50 and/or platform 82 to outerperimeter 53.

Compensation for forces exerted by a movable load present on upper deckframe 50 may be accomplished by providing an additional force in theform of fluid pressure, such as gas or hydraulic, to one or more fluidactuators 30 as a compensating pressure which may comprise a pressuresufficient to partially compensate for the movable load. Depending on apredetermined triggering condition, the compensating pressure may be setfor a known static mass of moving machinery/equipment, a knownunchanging mass of a consistent payload, a changing mass of aninconsistent payload, and/or an amount at, slightly below, or slightlyabove, any of these, or the like, or a combination thereof. Thepredetermined triggering condition may include a desired operationoutcome or a failure mode.

If the movable load comprises a changing payload, a mass calibrator suchas a a scale or other weighing device, or the like, or a combinationthereof may be incorporated and used to determine the requiredcompensation pressure. Payload compensation may then be changed based onthe determined compensation pressure.

Once the compensating pressure is set, an electrical actuator 20corresponding to a pneumatic actuator 30 is allowed to perform apredetermined set of functions. By way of example and not limitation,one or more of the set of pneumatic actuators 30 may be used to carrythe desired portion of both a static and a changing payload, permittingtheir corresponding electrical actuators 20 of the set of electricalactuators 20 to perform the desired motion functions with decreasedpower consumption than if acting alone.

It may be advantageous to statically pressurize one or more of the setof fluid actuators 30 so that it acts as a spring. The pneumaticpressure can be adjusted, e.g. initially or at some other point in time,such that a fluid actuator 30 changes its effective spring rate. Atother times, it may be advantageous to set a pneumatic pressure for oneor more fluid actuators 30 just below the fixed mass of upper deck frame50 and/or payload-bearing deck 80 such as when there is moving equipmentas opposed to changing payload. This fixed mass may include the mass ofupper deck frame 50 and/or payload-bearing deck 80 as well as itsassociated linkages, containers, benches, enclosures, electronics, andthe like, or a combination thereof. In this scenario, an electricactuator 20 cooperatively coupled to a fluid actuator 30 may be adjustedor otherwise allowed to lift the remaining portion of fixed mass plusthe entire load of payload beyond that and overcome the total inertia.Upon power removal, compensated motion base 1 may be allowed to settleto a minimal stroke, with or without payload.

At further times, it may be advantageous to set pneumatic pressures ofone or more fluid actuators 30 just above the fixed mass of the movingequipment, so that the compensated motion base 1 can settle out atmid-stroke with no payload.

At other times, it may be advantageous to set pneumatic pressures of oneor more fluid actuators 30 just below the mass of moving equipment andpayload. In these configurations, a characteristic of the payload may bemonitored and, if the payload remains constant between operations, thepneumatic pressure of one or more fluid actuators 30 fixed at thecalculated pressure]. However, if payloads vary, the pneumatic pressureof one or more fluid actuators 30 may be adjusted accordingly. Uponpower removal, compensated motion base 1 can be allowed to settle to aminimal stroke, with or without payload.

In yet a further configuration, pneumatic pressures of one or more fluidactuators 30 is set just above the total mass of the moving equipmentand payload so that the compensated motion base 1 can settle out atmid-stroke or above the total mass of the moving equipment and payloadso that compensated motion base 1 can settle out at maximum stroke.

Applications of compensated motion base 1 may including small payloadsystems such as for scientific and/or medical uses; amusement or otherride vehicles; stationary simulators; large theaters; military andaircraft trainers; or the like, or combinations thereof. Accordingly,controller 100 may be present and operatively in communication with oneor more electrical actuators 10, fluid actuators 30, pressure tanks 60,and the various sensors described herein and control each according tothe needs presented by the application.

The foregoing disclosure and description of the invention isillustrative and explanatory. Various changes in the size, shape, andmaterials, as well as in the details of the illustrative constructionand/or an illustrative method may be made without departing from thespirit of the invention.

What is claimed is:
 1. A compensated motion base, comprising: a. anupper deck frame comprising a predetermined outer perimeter; b. aplatform; and c. a set of compensated actuators disposed intermediatethe upper deck frame and the platform and arranged in a predeterminedpattern, each compensated actuator of the set of compensated actuatorscomprising: i. a base, comprising:
 1. a first attachment pointconfigured to be connected to the platform at a first predeterminedlocation with respect to the upper deck frame;
 2. a second attachmentpoint configured to be connected to the platform at a secondpredetermined location with respect to the upper deck frame proximatethe outer perimeter; ii. an electric actuator pivotally connected to thebase at a base coupler, the base coupler comprising a first base joint,and pivotally connected to the deck at a first joint; and iii. a fluidactuator pivotally connected to the base at a second base joint and tothe deck frame at a second joint pivotally connected to the first joint.2. The compensated motion base of claim 1, further comprising a set offluid supply tanks, each fluid supply tank of the set of fluid supplytanks operatively in fluid communication with a corresponding fluidactuator.
 3. The compensated motion base of claim 1, where thepredetermined pattern comprises being disposed evenly and radiallyoutward from proximate a center point of the upper deck frame to theouter perimeter.
 4. The compensated motion base of claim 1, wherein thefirst joint and the second joint are substantially co-located.